H2O Signature Stereo vs H20 Signature Mono Amps

I am in the process of downsizing my rig and am curious to learn more about the H2O amps.

Has anyone compared the signature version stereo amp to the signature version mono amps? If so, please share your findings in the comparing of the 2 set-ups?

Do the signature mono's perform that much better than the signature stereo to justify twice the price?

Is Henry coming out with a pre-amp? If anyone has info on this, please share what you know.

Are the H2O amps a fully balanced design?

I am strongly considering matching a good tube pre with solid state power amplification. If you have had success or failure doing so, with the H2O amps, please share your experiences.

The H2O is great for people who are upsizing, and even downsizing.

There are four H2O amps.

1) The Stereo H2O is a groundbreaking amp. It can handle any speaker load.
It handily controls the bass. It's mids are fluid, and articulate. The highs
simply natural. $2000

2) The Mono H2O amps improve on dynamics and separation. They are two
complete amps. For lighter loads, I would opt for the Stereo H2O. $4000

3) The S-250 Signature increases kick, and is somewhat quicker. $2800

4) The M-H2O Signature monos are the creme de la creme. They do
everything a little more. The reason is, there is more room in the mono amps
to apply added features. $5000

All H2O amps are fully balanced.

Strong tube preamps mate well with the H2O.
I'm thrilled with my Signature S250s. I had three of the original S250s for tri-amping and got the first Signature upgrade. It's definitely worth the extra cash and makes me wonder if Henry ought not skinny his line down to just the mono & stereo Signatures while offering upgrades for the earlier products.

My only concern with tube preamps is that some have very high output impedances (over 500 and up to 1500 ohms). The input impedance of the amp is set by the ICE module at 7-8 kHz. You really need to keep the preamp output impedance under 500 ohms otherwise you will compromise the amps bass response, which is one of its most stunning and arresting characteristics.

IMHO, of course.


One correction on the above. I beleive the Signature Monoblocks retail for $5500. The other prices sound correct.

As for anyone comparing the Signature Stereo to the Signature Mono's I would doubt there would be more than one or two, since Herny has just started making a Signature of the stereo version.

As for if the Sig mono's perform that much better than the Sig stereo to justify the price, that would be a question for Henry as to the sonic differences, and most likely the load of your speakers as well, your room size, your listening levels, etc. will help you decide whether or not you will need the mono's rather than a stereo unit.

Is Henry coming out with a preamp? I don't know. I know I heard his preamp design when I was there that he was working on. Whether it is anywhere close to the performance level he wants to achieve to bring it to market is not known by me. If memory serves me correct he has been building amplifiers for well over 10 or 12 years and he just brought his amps to market half a year ago... so I guess that would be another question for Henry.

The H2o Sig mono's I have do have balanced inputs. I have not used them and am not certain what a fully balanced design would entail... again I would redirect you to Henry.

As for yor question of success or failure mating a good tube preamp with his H2o's - I have had overwhelming success with the combination of the First Sound Presence Deluxe Mk II preamp going into the Signature Mono's. I am not sure how you quantify a "good tube preamp" - however I can tell you this combo leaves nothing to desire. Well not true, I still *do* desire my wife would let me spend more on albums and cd's and such... :)

Hope some of my limited insight helps.
I talked to Henry just before posting. I didn't mention the prices. Thank you Kirk. According to Henry, the Sig monos sit at the apex of the H2O line. The S-250 Sig is not the same amp, though Henry should be happy to see it surpassing expectations.
Henry quoted me $2500 for the Stereo version 6 months ago. Have prices gone down?
As far as I last heard:

S-250 - $2,500

S-250 Sig. - $2,800 ? first I heard was here (not sure)

M-250 - $4,000

M-250 Sig. - $5,500

I would assume Henry quoted you correctly and perhaps Muralman had a typo above...

In what way are you downsizing your rig?

The H20 stereo versions have about 1/2 the capacitor storage bank of the monos. That said, the stereo H20s still have more storage than many other amps - in excess of 70,000 uF per channel.

Could this extra storage capacity be wasted in your downsized system?

The stereo Signature model is essentially dual mono in a single chassis. It employs a separate transformer for each channel.

Between family & work, I do not have a lot of time to just kick back & enjoy my music these days. Therefore, I am trying to put together a 2-channel system that is musically satifying to my ears, but does not tie up the cash that I had in Rowland's 302 and Synergy IIi.

Tough to justify this level of gear, when some of that $ could serve so well in other areas of our home.

The challenge is on, as you can see what reference amplification my ears are accustommed to.
Game on. I will take odds on that Barrelchief as I was auditioning the Rowland 201's, 501's, and the 302 (heard it, wasn't in my price range) with the Synergy IIi before I stumbled upon the H2o's.

With that said, the Rowland 201's and 501's didn't compare to the 302 (obviously) and neither did the 201's or 501's compare to the H2o standard stereo IMHO. FWIW I think the 201's sounded better in the mids than the 501's, however the 501's did appear to have better control. The 302 is a different animal than either the 201 or 501. I was told by a Rowland rep that the 201 is 85-90% of the sound of the 302. I will have to respectfully disagree. However, perhaps the refinement, etc. is in that last 10-15%... it just didn't sound that close to me.

I would contact Henry and see if he has a *broken in* pair of Signature Mono's you can audition. Make sure he is aware you want a broken in pair, as I can tell you now, the sound change is drastic between a new unit and one fully broken in, especially in the mids being fleshed out and liquid as well as the air on the top end.

I haven't had the pleasure to compare the Sig H2o Monos to the 302, however if my memory serves me correct, and there is no impedance mismatch between the Synergy IIi preamp and the H2o's I think you will be pleasantly suprised.

Are you also looking to downsize on your preamp, as that is a very good preamp...
Hi Audiofankj:

I appreciate you sharing your experience.

I would describe as my "downsizing" as being in the "big picture" and not necessarily with every component...just looking to pull out a good chunk of $ and maintain an enjoyable 2-channel system.

Yes, the Synergy IIi is a very nice pre. However, with these changes, I am very interested in matching up a tube pre with SS power amp. One pre that has been recommended to sound great w/Ice amps (after rolling tubes) is the Aesthetix Callypso. I am open to suggestions.


Althought I've lived with both components for some time and I've never tried them with the H2O, I can certainly recommend the Transcendant Grounded Grid pre-amp and Phono Stage as outstandingly good values for the money. I think both would work very well with the S250 Sig. Tube rollers are welcome!

I have a Supratek Chenin that sounds wonderful with my H2O S-250 on my Scintillas. BOb
I personally use the First Sound Presence Deluxe Mk II to great effect. In general it is not a VERY tubey sounding preamp, it has the superb dynamics and low noise floor of a high end SS design, yet has the liquidity and harmonics of a good tube preamp. This mates very well with the H2o Sigs.

I was also considering the Chenin / Cortese as they also seem to be a great piece as well as over achiever for their price point.

The Aesthetix Callypso was also a preamp on my radar, however I have never seen/heard one in person...

I recently purchased the Sig S250 for $2800. I asked Henry about the sonic comparisions between the Sig S250 and the Sig mono 250. Henry told me that the Sig S250 sound almost as good as the regular M250s but that the Sig Monos sound best. However, he stated that the degree of difference between the Sig S250 and the Sig M250 diminishes with speakers which are an easy load. At 300 hours of break-in the Sig S250s are awsome with my ProAc D80s which can be driven with as little as ten watts. I cannot imagine better.
The stated-load related performance is consistent with the size of the capacitor bank - doubled in the monos. The power supply in the standard stereo unit looks similar to the power supply in the Signature monos shown in the picture over at 6 moons. It used to be that a mere 4 ohm load was considered demanding.

There can be other reasons for choosing monos such as a pre-existing cable set or aesthetics.

Of course it would be fun and real interesting to compare a pair of the S250 Sigs passively biamping a bitchy load with a pair of the Sig monos. Same price point.

Kinda like comparing a chipped out Audi S4 2.7T with a stock BMW M3....let the fun begin!

does h2o have a web sight? If not can their phone or address be posted here?